In some proposed disk drives, such as magnetic disk drives, a thermally-assisted magnetic recording system is used to achieve improved recording density, lower noise, and high resistance to thermal agitation. In these magnetic disk drives, medium heating means, such as an optical or electron beam, is located near a recording magnetic pole of a magnetic head. In recording operation, a medium is locally heated by the medium heating means so that HcO is reduced to the level of the head magnetic field.
It is important for one such magnetic disk drive to apply a recording magnetic field to the medium, being heated or having just finished being heated, to complete recording before the medium is cooled. It is also important to prevent the recording magnetic field from being inverted by the influence of thermal agitation before the medium is fully cooled.
The thermally-assisted magnetic recording head used in the conventional magnetic disk drive has a problem that the medium cannot be rapidly cooled after thermal laser application, so that recorded data is degraded, and hence, the linear recording density cannot be increased. Further, some heads for photo-magnetic recording comprise an airflow path for cooling a slider. If such magnetic heads are used in a magnetic disk drive, however, their cooling effect is too small to easily suppress degradation of recorded data.